/* 先删除默认的内外边距 */
* {
    margin: 0;
    padding: 0;
}
html {
    -webkit-text-size-adjust: 100%;
    -ms-text-size-adjust: 100%;
    font-size: 62.5%;  /* 设置过根节点的文字大小后，所有子节点的文字大小全部相对于根节点计算，html为10px */
  }
  body, input, button, a, textarea, select {
    margin: 0;
    font-family: "Helvetica Neue", Helvetica, "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
    font-size: 1.4rem;
    line-height: 1.5;
    color: #333;
  }

  a,
  u,
  s {
    text-decoration: none;
  }
  a:hover, a:focus {
    text-decoration: none;
  }
  a:hover {
    filter: alpha(opacity=90);
    opacity: .9;
  }
  
  dl, ul, ol {
    margin: 0;
    padding: 0;
    list-style: none;
  }
  input button select {
    outline: none;
  }
  fieldset, img, iframe {
    border: 0;
  }
  
  i, em {
    font-style: normal;
  }
  
  label {
    font-weight: normal;
  }
  
  h2, h3, h4, p, dl, dt, dd {
    margin: 0;
    padding: 0;
  }
  img {
    width: 100%;
    margin: 0;
    padding: 0;
  }

  body, input, button, a, textarea, select, dl, ul, ol, li, h2, h3, h4, p, dl, dt, dd, span, div {
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
  }
  
  /* css3过渡动画效果 */
  .trans {
    -webkit-transition: all 0.3s;
    -moz-transition: all 0.3s;
    -o-transition: all 0.3s;
    transition: all 0.3s;
  }
  
  /* 文本对齐 */
  .tc {
    text-align: center;
  }
  
  .tr {
    text-align: right;
  }
  
  .tl {
    text-align: left;
  }
  
  /* 去掉浏览器focus默认外边框 */
  a:focus, button:focus, input:focus {
    outline: none;
  }
  
  /* 单行文字溢出省略号 */
  .ell {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    word-break: keep-all;
    word-wrap: normal;
  }
  
  /* 清理浮动 */
  .fn-clear {
    zoom: 1;
    /* for IE6 IE7 */
  }
  .fn-clear:after {
    visibility: hidden;
    display: block;
    font-size: 0;
    content: " ";
    clear: both;
    height: 0;
  }